Removable plug for boilers and the like



APPLICAT'ON FILED )ULYZE. I916.

Patented Aug. 10

llz'am H WILLIAM H. WINSLOW,

OF CHICAGO, ILLINOIS. ASSIGNOR T0 WINSLOW SAFETY HIGH-PRESSURE BOILERCOMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

REMOVABLE PLUG FOR BOILERS AN THETJKE.

Application filed m 26,

To all whom it may concern:

Be it known that I, WILLIAM H. WINSLOW, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented. a certain new and useful Improvement in Removable Plugs forBoilers and the like, of which the following is a full, clear, concise,and. .exact description, reference being had to the accompanyingdrawings, forming a part of this specification.

The present invention relates to removable plugs for boilers, or thelike.

It is well known in the art that washout plugs are provided in mostboilers to allow of removal of mud and scale when the boiler is cleaned.In low pressure boilers the ordinary brass plug that is threaded intothe shell of the boiler is fairly satisfactory. Such plugs are notpractical for high pres sufe boilers, especially of the type shown in mycopending applications, Serial No. (356,179, filed October 23rd, 1911,derial No. 8ell,445, filed May 28th, 19H. Serial No. 859,157, filedAugust 29th, llll-l, which are designed to carry regularly hill) or (MUlbs. pcr square inch steam pressure. Not only is the pressure too greatbut thc temperature is so high that the diflcrence in thermalcocliicient of expansion destroys thc valuc oi' the plug as a closure.Screw plugs are further impractical because they must be d awn up sotightly for high pressures that rcmoral and'inscrtion of a. plug largeenough to allow access to the interior of the boiler requires too muchpower. In other words it becomes a task that is beyond the repair nianor cleaner.

The object of my invention is to provide an improved plug which iseasily put in place or IQIIHWfll and which will remain tight even underhigh pressure. I shall now describe more fully in the followingspecification, in connection with the accompanying drawings, oneembodiment of my in rention.

The single figure of the drawings is a fragmentary section oi part of aboiler showing the plug in position on its seat.

In boilers of the type set out in my abovementioned co-pendingapplications, it is desirable to clean the tubes, especially thelowermost tubes in each section where mud and Specification of LettersPatent.

Patented Aug. 10. 1920.

1915. Serial N0. 41,812.

scale are most likely to deposit and settle.

The tubes 1 and 2 which may form the lowermost tubes in the section ormay [ii any other tubes that it is desired to clean.

are welded to the header 3 by autogen'ous welding so as to form theseparts into a unitary integral structure. The tubes and headers are madepreferably of steel tubing. Hollow b osscs 4: and 5 are formed on theheader 3 1n alinement with the tubes Land 2 and on the opposite sidethereof so that the opening in these bosses 4 and 5 are in ahnernentwith the openings in the tubes 1 and 52. These hollow bosses may beformed of thimblcs welded to the header 3, or where the particularportion of the header 3 is formed of astecl casting, these hollow bossest and 5 may be made of cast metal integral with the rest of the casting.The hollow boss has a conical seat 6 of rather a small degree of taper.The boss is counterbored and screw-threaded at 7 to receive a plug 8. Aconical plug 9 having a squared shank 10 is seated upon the annular seat(3 in thc boss 4. The squared shank 1 e.\'- tends into a. recess ll inthe threaded plug H and has its outer end which is squared oil restingagainst thc bottom l2 of the cavity H for holdinglhc plug 9 upon itsscat ii. The conical plug 9 is faced with a iackrt 13 of a tough andFairly soft metal. preterably copper. This jacket of copper l3 extendsovcr the front face of the plug 9 and ovcr the conical portion in theform of a cup or pan and is folded over at the bark of the plug as shownat 14. This jacket forms an impcrloratc conical gasket which forms arcry tight closure bctwccn the tapered plug 9 and the scat (3. In factthis copper jackcl; forms the real closure, the plug 9 bcing mcrcly avehicle lot it and a means for holding it in place aftcr it is applied.

The action of the dcvicc entirely diflcrcnl from a screw plug or from aconical valrc, as hcrctoi'orc constructed in the art. It is to bedistinctl noted that the conical plug 9 docs not rcrolvc and has a.longitudinal movement only. The plug 9 with the copper facing isinscrtcd into the opening and placed loosely on the seat 6. Thescrew-plug 8 is then screwed into the threaded part T and the squaredshank 10 of the plug 9 rests against the hottorn 12 of the cavity 11,this bottom 2 being faced off accurately so to hold tl conical plug 9 inexact alinement in the axis of the Jobs 4. As the screw-plyg 8 is drawnup, the plug 9 is forced along the ani" of the tube driving the sameforward against thc conica'l seat 6, gripping the copper gasket 13firmly against the seat so as to form a very tight joint. The area ofcontact between the bottom 12 of the plug 8 and the end of the shank 10is much smaller than the area of contact between the plug 9 and thecopper gasket 13, or between the copper gasket 13 and the seat 6, and asa consequence the plug 9 does not turn when the screw-plug 8 is drawntight.

Due to the fact that the gasket or jacket 13 is imperlorate, it isnecessary to make only one steam tight joint and that is be tween thisgasket and the seat 6. This is a great :uh antagc, as is readilyapparent.

'hen the plug 9 is to he removed, the screiwplug 8 is unscrewed. Thismay readily be accomplished as the threaded portion 7 consistspreferably of straight threads and as soon as the pressure upon the stem10 is relieved, the plug 8 may readily be withdrawn by hand. A piece ofpipe having a squared end or a tube having a squared socket is slippedover the shank 10 of the plug 9 and the plug is wahhled on its seat bysidewisc motion of the stem whereupon the same may readily be withdrawnwithout any trouble. The shank 10 need not be square and may he maderound or in any preferred form.

Due to the short distance which the copper gasket or jacket 13 moves onthe seat (5, the copper does not have an opportunity to hall and spoilthe joint, as would he the case if the plug 9 were rotated whenIii-ought upon its seat. The plug 9 may he madc of cast iron or of steeland in either case the co efficient of expansion due to changes intemperature would he suhstantially the same as that of the soft steelwhich forms the seat (3. The copper jacket 13 is of such smalldimensions that the dilference in expansion would be inappreciable andas a consequence the joint always remains tight. The end f the shank 10is squared so as to hear against the surface 12, these two surfacesbeing at right angles to the axis of the boss 4. As a consequence it isimpossible to insert the plug i) in a skewed manner for as soon aspressure is brought upon the stem 10 by means of the plug 8 the plug 9will he si uarcd up with the axis'of the boss and will he properlyseated upon the seat 6.

The space between the hollow plug 8 and the back edge of the conical dugS) is very slight, lacing only about onesixteenth of an inch so that theconical plug cannot gct started crookcd on its scat. if i! should startcrooked the rim of the hollow plug en en;

would touch the back edge of the plug 9 and would straighten it upon itsscat. This distance has been exaggerated in the drawings order to makeclear that there is norxixlly no contact between the hack 'cdge of t tconical plug and the front parts of the screw plug.

\Vhile 1 have shown one specific embodiment of my invention, 1 do notintend to be limited to the prccisc details of construction shown anddescribed, as changes, variations and modifications will immediatelysuggest themselves to those skilled in the art and I. consider the sameto come within the spirit and scope of my invention.

hat rclaim as new and .desire to secure by Letters Patent of the UnitedStates is the following 1. In combination a hollow boss hauing aninternally threaded portion and a conical scat adjacent said threadedportion. an internal conical plug in said seat, guiding means on therear of said conical am for guiding the same upon said conical seat. ascrew-plug engaging said conical plug and clamping the same against saidseat, the lateral walls of the boss being impcrforate.

2. In combination a hollow threaded boss having a conical seat adjacentthe threads, amonical plug, guiding means on the rear of said conicalplug for guiding the same upon said conical seat, a soft metal gasketbetween the plug and. the seat, a screw-plug engaging the threads andholding said conical plug and the gasket upon the seat, said gasketbeing formed of an imperforate cup entirely rinelosing the front andconical sides of said conical plug.

3; In combination a hollow internally threaded boss having an internalconical seat adjacent the threaded portion, a hollow conical cup shapedgasket of soft metal engaging said seat, a solid metallic conical plugin said gasket and holdin the same against said seat, a threaded plugfor engaging the threads in said boss and for clamping said conical plugand said gasket against said seat, and guiding means on the rear of saidconical plug for guiding said plug and said gasket upon said seat.

4. In combination a hollow boss having an annular conical seat therein,a coi'iperating plug for engaging said seat, said boss having aninternally threaded portion, a threaded plug cooperating with saidthreaded portion, said plu r having a stem of reduced diameter, sai stemhaving its end have only in engagement with said threaded plug and asoft metal gasket between said seat and the plug cooperating therewith.

5.-ln combination a hollow boss having a conical sent, a threadedcounterhore, a. conical )lug having a stem, an imperforate metal gas etcovering the front and the conical" sides of said plug, a threaded plughaving a l'ii'ish therein, said recess adapted to r'- ceire' loosely thestem of said conical plug, the bottom of the recess normally pressingagainst the end of the stem.

(3. In combination a hollow boss having a solid metallic conical seattherein and a threaded portion adjacent said seat, an imperi'orateconical gasket engaging said seat, a roniral plug having its front andconical sides covered by said gasket, said plug having a stern extendingat right angles to the body thereof, said stem having a square end, ahollow threaded plug for engaging the threads in said boss, the hollowportion of said plug having a fiat bottom wall for engaging the squareend of said stem, said plug completely filling said gasket and formingthe sole engage ii ant between the hollow plug and the conical plug.

7. in rombination a header, a tube joined thereto andhavingcommunication therewith. a hollow boss on the opposite side of saidheader in axial alinenien t with said tube. said hollow boss having aseat therein and a threaded portion adjacent thereto. a conical plubearing on said seat, said plug having a stem projecting in axialalinement with said boss, a screw plug for engaging the threaded portionof the boss, said plug having a recess therein, the bottom wall of saidrecess engaging the end of said stern and Towing the conical plug uponits seat, said engagement forming the sole engage ment between saidplugs.

H. in munbination a closed vessel, :1 i101- low boss on said vesselhaving ifilflmlflllflth tion with the interior thereof. said boss havinga acrew-threaded portion and a conical seat portion. a. conical plughaving a. facing of soft tough metal forming in cooperation with saidseat a closure for said hollow boss. said plug having a stem extendingaxially tlu-rel'rom. said stern having a bearing surface upon the endthereof, a screw-plug for engaging the threaded portion of said boss,said plug baving a cooperz'iting engaging surface for allning saidclosure plug with said Hlili. the engaging surfaces being of less areathan the area of engagement between the Wu and the plug and forming thesole contact between the onical plug and the sercu plug,

h. in roinbination a conical plu; compris ing an enlarged conicalportion and a stem extrudiiug' axially thercl'rom and a gasket formed inthe shape of a pan, said gasket embracing uid enlarged conical portionand having its rinl folded against the side thereof adjacent the pointwhere said stem joins said enlarged portion.

h In combination a conical seat, a plug comprising an enlarged conicalportion and a. reduced stem portion attached thereto, an iuuacrforategasket inelosing said enlarged (onitul portion and engaging said seatand means for holding). said plug iunl gasket against saulseat, saidmeans engaging the end of said stem only.

ll. In combination a conical annular seat,

a solid metallic plug having an enlarged conical portion, an imperforategasket engaging said conical seat and formin a C10- surw therefor, meansfor holding sald plug and said gasket against said seat, said plughaving means coiiperating with said holdin means to aline the same uponsaid seat and having a stem of reduced diameter adapted to engage saidholding means at its end only.

12. In combination, a conical seat, a conical plug for. engaging saidseat, said plug having a short stem of reduced diameter liiiojettlilgfrom the rear thereof, said stem being faced off flat at right angles tothe of the plug, a screw threadedholding member having a flat face forengaging the flat end of the stem, the area of engagement between thestern and the holding member being substantially than the engaging areabetween the conical plug and seat to insure relative rotation betweenthe stem and the holding member and to prevent rotation of the plug onits seat when the holding member is screwed into or out of engagementwith the stem.

13, In combination, a hollow boss, a coniral seat in said boss, athreaded counterbore between said seat and the end of said boss, a solidmetallic plug member having a conical head adapted to bear upon saidconical seal. an imperforate metal gasket embracing said conical head, ascrew plug threading into the counterbore and adapted to hold said plugmember tight against said conical seat. a short stem of reduced diameterprojerting from the rear of said conical head. said stem being finishedoli fiat at right angles to the axis of the pluginember, said steinfitting loo ely into an enlarged recess in the end of said srren' plumthe area of engage nn-ni between the. stem and the bottom of thel'cri'ss being substantially lBf-S than the en gaging area between theconical plug and its seat to insure relative rotation between the sternand the screw plug and to prevent r tation of the plug member on theconical seat when the screw plug is started into and out of engagementwith the plug member.

ll. In conihirmtion, a steam header, a circulating tube intersecting oneside of said steani header. a hollow boss on the other side of saidheader and eo-extensive with said circulating tube, said boss having itsends internally threaded, a conical. seat in said hollow boss at theend" of said thr ad, a solid metallic plug member having 21 conical headadapted to bear upon said conical seat a soft metal gasket formed in theshape of a pan embracing said conical head and having: its rim crimpedover the back thereof, a screw plug engaging in the and mi suit svmrwmrmaily (mi (If (*x'lgugelh.

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